GB1089347A - Air sifter - Google Patents

Abstract

1,089,347. Pneumatic separators. POLYSIUS G.m.b.H. Aug. 27, 1965 [May 18, 1965], No. 36847/65. Heading B2H. In an air classifier wherein material is separated into coarse and fine fractions by means of an upward ail current, a fan 10 for inducing the air current, a rotating vane assembly 11 which defines the degree of fineness of the fine particles and a scatter-plate 12 for throwing the material outwardly are carried below one another in that order on a driven tubular member 8, 9 which is rotatably mounted in upper and lower bearings 6, 7, the fixed parts of the bearings being mounted on a non-rotatable common axle 2 which is suspended in pendulum fashion from the top part 1a of the classifier and is held at its lower end by radially extending struts 3 which are radially adjustable by means of nuts 5 so that the bearings can be easily brought into strict axial alignment. The tubular member consists of tube parts 8, 9 rigidly held together and is driven by means of a pulley 13 connected to the part 8. In operation, the fan 10 maintains an air current as shown by the dotted lines in the figure. Material to be classified and air are supplied from outside the classifier to the interior of the classifier. The material is fed on to the plate 12 and is scattered thereby into the upward air current. The major part of the coarse particles, due to their relatively high specific gravity, are not affected by this air current and fall into the funnel 4. The remaining material is, carried upwards by the air current and enters the counter-vane system 11 which rejects coarse particles centrifugally but allows the light particles to pass through and be discharged into the space between the casing 1 and the funnel 4.